I am looking to purcase a C4 and I need some info, such as was the 4+3 tranny any good ?

when did the six speed come out ?

how much would a red rag top C4 with a six speed and moderate mileage ?

how much better is the LT-1 to the L98 ( did either egine have any aging problems ?)

how good is the LT-5? ( is the LT-4)

what is this I hear about rotting floor pans? (is that easy to fix)

 

The 4+3 transmission did its job. The more modern 6-speed is better.

I'm not sure when the 6-speed came out, but I believe about the time they went to the LT engine series.

I've seen reasonable convertible C4s for $10-$14k.

I know the LT series is a deriavative of the L98 and earlier. I know many, many parts are interchangeable or close to it, but I have always regarded them as two different engines: there are enough differences.

LT-5?

The LT-1 is good.

The LT-4 (335 HP) is very good: basically an LT-1 with the equivalent of about $2500 in work you could do yourself on heads and so forth that adds ab out 25 HP or so.

Rotting floorpans are not easy to fix, they are easy to patch and live with and stay pissed off about for a while, but . . .


One thing you have not mentioned is electrical; early C4s had electronic dashboard (which I don't like and a lot of owners didn';t like) and which was a pain in the butt with glitches and failures), and they had some nuisance elctric problems throughout. (My brother had a new '84, believe I know).



Recommendation: Let age, not just the condition you see, be a major factor: find one that is both in good shape and not too old.
There are well-cared for, loved, 'vettes that come on the market. Wiat until you find a good one.
Body should be solid. Look for signs of water leaking into the car and down into the floor (just think about where you'd go if you were a drop and got in around the convertible top or windo seals, they dribbled down -- then serach there). New carpets, replaced padding, are a sign the owner might be trying to to cover up rot from leaks (or, maybe he or she is just trrying to make the car attrractive to sell, so don't hold that against them, but check).
Check out the fiberglass for repairs (ripples, underneath patches.
Dashboard has analog instruments. I recommend to stay away from the digital dashboard.
Rear end and suspension and steering in good shape. Bushings should be tight. Power steering, all coolers, should have no leakes.
LT engine. 1 or 4 doesn't matter: you can mod the LT1 to LT4 levels, or more, power for about $1500+
If on a budget I would not pay extra for an LT4.
6-speed trans or a 4-speed auto, your choice. Drive it and make sure it shifts well. 2nd and 3rd gear syncros tend to go first in 6-speeds that have been abused.
Expect to spend 10% of what you pay for the car, very soon after buying it, on just small stuff that does nothing but fix some things you didn't know was broken.

 

Hello my friend.The 4+3 was,well,troble prone,especially on the '84 and '85 models.The six-speed first came out in 1989 with the L-98 and a few prototype ZR-1's.Basically,all the C4's engines are very stout as long as maintenance is up to date,although the L-83 Cross-Fire was a bit troublesome.The L-98 is a torque monster,it has more low-end torque than the LT-1 is replaced,although the LT-1 has more(50) horsepower and revs more freely.The LT-4 is an improved version of the LT-1 with roller rockers,a different cam and intake manifold helping it put out 330HP over the LT-1's 300.The LT-5?? That is a completely different beast....4 cams,32 valves,all aluminum construction and an 8000rpm redline,if I'm not mistaken,and power between 375 and 405HP depending on the year.The '90 to '92 cars had 375 along with 2-bolt mains,while the '93 to '95 had 405,along with 4-bolt mains.....it's a monster engine....but a very expensive one to repair if not properly taken care of.Hope this helps you,your friend,Joe.